Power driven vehicle for disabled

ABSTRACT

A power driven vehicle for disabled, particularly for children, and which incorportaes a motor driven chassis module, a seat module and an accumulator module, wherein the chassis module incorporates two wheel pair units, which are disconnectable from each other and constitute a first, front wheel unit and a second, rear wheel unit, one of the wheel pair units, preferably the first wheel unit, incorporating two steering and driving units acting individually upon one wheel each, the second wheel unit being composed by a central beam, one end of which is connectable to the first wheel unit and having at its other end a yoke pivotably supported transversely to the longitudinal direction of the vehicle, and having at its free ends wheels supported in bearings, and said seat module being centrally arranged on the beam, whereas said accumulator module is attached on both sides of the beam, between the pairs of wheels.

The present invention relates to a power driven vehicle for thedisabled, particularly for children, and which incorporates a motordriven chassis module, a seat module and an accumulator module.

BACKGROUND OF THE INVENTION

Vehicles for disabled children have hitherto at best consisted ofdiminished size, conventional wheel chairs for adults. These wheelchairs are not adaptable or not readily adaptable to the development ofthe child, i.e. its physical development as well as the development ofits possible handicap, during the childhood; and the wheel chairstherefore neither take into consideration the child's requirement forplay, nor do they meet the demands from the nursing staff for ease ofhandling and low weight.

Wheel chairs for disabled, which are designed in modules are known, e.g.from SE-C-331 884, and they consist of a chassis, incorporating a motor,wheels and battery box, which parts form a continuous unit of largeweight. A seat module can be attached to the chassis, which seat modulecan be common for several different types of chassis, for providing e.g.an indoor wheel chair, a stationary or a semi-stationary chair.Conventional, electrically powered wheel chairs are very heavy andexpensive.

PURPOSE AND MOST ESSENTIAL FEATURES OF THE INVENTION

The purpose of the present invention is to provide a wheel chair, whichconsists of several different parts--modules--, each one beingexchangeable for bigger ones so that the wheel chair may "grow" togetherwith the child. The wheel chair with some simple manipulations also bedismantled into easily manageable parts, which make it possible to usethe wheel chair indoors as well as outdoors. Due to an exchange systemit shall be possible to exchange different modules for bigger modules orfor modules particularly adapted concurrently with the development ofthe child's handicap.

The module system will facilitate service, when it will be possible toreplace a defective module, e.g. by the child's parents, withoutsubstantial difficulties , so that the wheel chair never must be out ofuse for any substantial period of time. A further purpose of theinvention is to provide a wheel chair, wherein the child can have bothfloor contact, i.e. participate in activities at floor level, as well asbe sitting at a table, whereby the child himself or herself shall beable to adjust not only the height position of the vehicle but also themaneuvering of the entire vehicle. These tasks have been solved in thatthe chassis module incorporates two wheel pair units, which aredisconnectable from each other, a first wheel unit, preferably being afront wheel unit and a second wheel unit, preferably being a rear wheelunit. One of the wheel pair units, preferably the first wheel unitincorporates two steering and driving units acting individually upon onewheel each. The second wheel unit comprises a central beam, one end ofwhich is connectable to the first wheel unit. Its other end a yoke ispivotably supported transversely to the longitudinal direction of thevehicle. Its free ends have wheels supported in bearings. The seatmodule is centrally arranged on the beam. The accumulator module isattached on both sides of the beam, between the pairs of wheel.

DESCRIPTION OF THE DRAWINGS

The invention hereinafter will be further described with reference tothe accompanying drawings, which show some exemplary embodiments.

FIG. 1 shows in perspective a wheel chair according to the invention asseen obliquely from the front side thereof.

FIG.2 shows in perspective an exploded view of the different modules ofwhich the wheel chair according to FIG. 1 consists.

FIGS. 3 and 4 show views analogous with FIG. 2 of two modifiedembodiments.

FIGS. 5 and 6 show in views from underneath and from the side a furthermodified embodiment of the wheel chair according to the invention.

DESCRIPTION OF THE EMBODIMENTS

The wheel chair according to the invention consists of a chassis module11, a seat module 12 and an accumulator module 13. The chassis module 11incorporates two wheel pair units 14 and 15, one 14 of which isconstituted by a drive unit 16, consisting of two coaxially arrangedD.C. servo motors 17, which via one gear box 18 each drives one drivingwheel 19 each. The seat module 12 incorporates the implement with whichthe vehicle shall be used, e.g. a chair if the vehicle shall be a wheelchair. Instead of the chair it is possible to use a robot or the like asthe implement.

The second wheel pair unit 15 forming part of the chassis module 11,consists of a central, longitudinal beam 20, having at one end, itsrearmost end, a bearing 33 arranged in the axial direction of the beam,on which bearing is pivotably supported a yoke 21 on the at both of itsends supports one wheel 22, which is freely rotatable about a verticalshaft. The beam 20 of the rearmost wheel pair unit at its end facingaway from the yoke 21 is interconnectable with the drive unit 16 bymeans of connecting means 23, consisting of a male portion 24 fitted tothe beam and a female portion 25 fitted to the drive unit. Theconnecting means is a so called quick-coupling, which by a handgrip 26may be locked thus that the portions are rigidly interconnected.

The beam 20 also forms an attachment at one hand for a column 27, towhich the seat module 12 is attachable by means of a connecting device28 designed as a quick-coupling, and on the other hand for twohorizontally arranged attachments 29 for supporting one battery box 30and 31 each. The column 27 may consist of a longitudinally resilientmember forming in effect a gas spring, which is arranged in such amanner, that the connecting device 28 may be adjusted to differentlevels. The column 27 may also be an electrical actuator, designed sothat the seat module 12 can be raised and lowered by the handicappedperson.

The maneuvering of the wheel chair is effected by aid of a so called joystick 32, provided at one arm rest of the seat module 12, thus that itis within comfortable reach for one hand of the disabled child.

At least one of the battery boxes 30 or 31 respectively contains besidethe accumulators also an electronic system, having both a steering and asurveillance function. The system incorporates the two motors 17 of thedriving unit 14, which e.g. are equipped with optical speed sensingsystem and electromagnetically operated parking brakes. The system isdesigned thus that the brakes will be applied against the brake discs aslong as the wheel chair is not activated and in this manner the motorshaft is prevented from rotation. The parking brake of the wheel chairthereby is activated and the chair can not move. When the joy stick 32is moved out from its neutral position an electro magnet will move thebrake arm from its braking position and the parking brake is released.In order to avoid the parking brake being applied as soon as the joystick passes its neutral position there is introduced a time constant inthe electronic system, which may be e.g. 5 seconds, during which timethe joy stick must be in its neutral position to result in activation ofthe brake. The parking brake can be mechanically released, but not byplaying children, to be certain that the wheel chair shall not begin tomove unintentionally.

The embodiment according to FIG. 3 differs from the proceding embodimentin that the beam 20 is designed as a steel tube frame, which is equippedwith an inclined guide 34, along which the connecting device 28 of theseat module 12 is displaceable. The guide 34 is so arranged, that itextends over the servo motors 17 of the front wheel pair unit 14,whereby the chair in its foremost position is situated at such a lowlevel, that the child can pick up objects from the floor.

In the embodiment according to FIG. 4 the beam 20 is constituted by asheet metal structure, by which the column 27 is tiltable to differentinclined positions about a shaft journal 35 and is arrestable in suchdifferent positions by means of an arresting means 36. The rearmostwheel pair unit 15 also in this embodiment is pivotable in relation tothe beam 20 about a bearing 33.

In certain cases it may be necessary to use four wheel drive, which canbe obtained by providing a drive unit 16 at both wheel pair units 14 and15. This is shown in the embodiment according to FIGS. 5 and 6, whereinthe beam of the chassis module 11 is two-part, whereby between the parts11A and 11B is provided a hinge joint 37 formed as a so called waiststeering. Between the chassis parts 11A and 11B is provided an actuator38, which is spaced apart from the pivot center of the hinge joint 37and adapted to provide mutual rotation between the two chassis parts 11Aand 11B.

The vehicle according to this embodiment is like the preceedingembodiments provided with a bearing 33 about which one of the wheel pairunits 14 is pivotable about a horizontal shaft. The foremost chassispart 11A is furthermore equipped with an inclined guide 34 forsupporting the seat 12 of the vehicle and providing a height adjustmenttherefore.

As the wheel chair is subdivided into modules it is possibleconcurrently with the physical development of the child but also in viewof the development of the child's handicap, to adapt each separatemodule to the prevailing situation. The module structure furthermoreresults in that each separate part will have rather low weight and beeasy to handle and can be carried by one person. Also when transportede.g. in a passenger's car the collapsible design is of particularadvantage, and this also applies to the situation when any module shouldbecome defective or need service.

The invention is not limited to the embodiments shown but a plurality ofvariants are possible within the scope of the appended claims.

It is thus completely within the scope of the invention to combinestructural details from one embodiment with corresponding details fromanother embodiment, but also a combination of details from differentvariants are possible.

We claim:
 1. A power driven vehicle for disabled, comprising a motordriven chassis module, a seat module and an accumulator module, thechassis module incorporating two wheel pair units which aredisconnectable from each other; the wheel pair units comprising a frontwheel unit and a rear wheel unit, the front wheel unit comprising twosteering and drive units each acting individually upon one wheel, andthe rear wheel unit comprising a central beam, one end of the beam beingseparably connectable to the first wheel unit, the other end of the beamhaving a yoke pivotally supported transversely to the longitudinaldirection of the vehicle; the rear wheel unit having at its free endswheels supported in bearings; the seat module being centrally separablyarranged on the beam; the accumulator module being separably attached onboth sides of the beam, between the two wheel pair units.
 2. A vehicleas claimed in claim 1, wherein a vertical heigth adjustable column isalso vertically and pivotally supported on the beam, the column having afree end which is fitted with a connecting device for detachableconnection of the seat module, and the column is positionable indifferent inclined positions.
 3. A vehicle as claimed in claim 2,wherein the column incorporates an actuator for raising and lowering theseat module.
 4. A vehicle as claimed in claim 1, wherein the beam hastwo lateral sides, on both lateral sides of the beam are loop-shapedattachments for supporting one detachable accumulator box each, and arespective accumulator box on each of the attachments.
 5. A vehicle asclaimed in claim 1, wherein on the beam is provided a guide, the guidebeing inclined down towards the drive unit a connecting device of theseat module is displaceable along the guide, such that in its foremostposition, the connecting device is situated mainly just above the firstwheel unit.
 6. A vehicle as claimed in claim 1, wherein the beam of thechassis module comprises two parts, and a hinge connecting the twoparts.